You have just identified an SEO service that isn't worth the money they want you to pay them, or a scanner produced by someone who didn't get updated with the reality that the Meta Keyword tag got dropped a decade or more ago as search engine spammers used it to mostly get porn to show up for non-porn searches.
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Fiasco LabsJun 29 '13 at 22:21

Although the keywords are not used by Google, some other search engines may use it. So, it's not a horrible idea to include a keyword meta tag. It won't hurt - assuming they are correctly implemented. And although Google says they don't use it for search rankings, that doesn't mean they don't look at it as a clue to a site that is trying to use it inappropriately.

Not a good idea, Bing uses Meta Keywords as a spam indicator. One of their online representatives says that it's one of the items taken into consideration in determining that the Bing search bot is being spammed per a direct conversation.
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Fiasco LabsJul 7 '13 at 4:45